commentariolum

commentārĭŏlum, i, n. (-lus, i, m., Hier. Ep. 149, 1), dim. [commentarius],

a short treatise , brief commentary : hoc, Q. Cic. Pet. Cons. 14, 58; of dub. form, abl. plur ., Cic. Fin. 4, 4, 10; id. de Or. 1, 2, 5; id. Phil. 1, 7, 16; Quint. 1, 5, 7.